To achieve optimal performance of a microphone array (or any other grouping of microphones), each microphone in the array must be calibrated. Typically, microphone calibration involves measuring the gain of the microphone. During automatic microphone array calibration, gain measures of each microphone in the array are utilized to determine various parameters of the array. Even minor deviations may affect this measurement and, therefore, the parameterization, thereby decreasing the effectiveness of subsequent calibrations. Thus, existing solutions for microphone array calibration require measuring gain in an echoless chamber to be effective.
The need for anechoic (echoless) chambers during parameterization presents various difficulties to microphone array users. In particular, the person who performs the parameterization may not be able to conveniently move echoless chambers to the location of the microphones (or vice-versa). In particular, because chambers used for parameterization must typically be much larger than the setup (microphone array), the microphone array must often be moved to the chambers. However, moving the microphones to the camber is not always possible. For example, nearby echoless chambers are not always available.
Additionally, the requirement to test and calibrate microphones only in echoless chambers may prove challenging when testing the microphones in a real world environment. A user may wish to parameterize a group of microphones once the microphones have been set up in an echoic area if, for example, the user wishes to ensure that the microphone array is still prepared after being moved to the location in which it will be utilized in and/or after repositioning any of the microphones in the array. Requiring users to place the array back in an echoless chamber after such modifications may delay use of the array.
It would therefore be advantageous to provide an efficient solution for calibrating an array of microphones on-site.